JPH0671865A - Plant for supplying pressurized gas to printing press system driven by pressure medium - Google Patents

Abstract

PURPOSE: To enable pressure to be appropriately supplied to a system against the actually required amount of a pressure medium in accordance with the lapse of time to be spent for a process underway in a printing press. CONSTITUTION: At least one pressure storing tank 12 and one sensor 19 for measuring pressure are assigned to each of system 11. The pressure storing tank 12 is radially connected to at least a single compressor 7 through an electrically driven pressure medium distribution/supply device. In addition, an electrical control part 20 is provided which is connected to the sensor 19 for measuring pressure and the mechanical control part of a printing press 1, and the electrical control part 20 controls drive motors 6 for the distribution/supply device and the compressor 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic supply plant for a printing press and a sub-unit provided before or after the printing press.

[0002]

It is known in printing presses to carry out a large number of working steps by means of a pressure medium driven system. For example, pressure supply plants are used for air pressure regulation cylinders, ink and dampening water pumps, as well as supply from blowers and suction devices. A simple plant consists of a compressor that feeds a compressed air tank and annular piping. Each printing unit and loads of the paper feeding device and the paper discharging device (devices that consume the power of the pressure medium) are connected to the annular pipe via valves. Increasing the number of printing units and mechanical units provided before or after the printing units increases the number of pressure medium loads and leak points. As a result, the compressed air requirements are increased, and the compressors and tanks must be sized accordingly in terms of feed capacity and storage capacity, in case of any emerging load. However, a compressor with a large feeding capacity and a tank with a large storage capacity are costly. Moreover, if the predetermined limit value for the product of pressure and volume is exceeded, the pressure store will belong to a plant that is obliged to monitor, which will result in additional costs for operating the plant. further,
It is structurally inconvenient to determine the dimensions of the compressors and tanks of each printing machine according to the number of loads according to the optimum characteristic values. If so, multiple compressors and tanks would be needed, as they would be inconsistent with rational construction.

The consumption of pressure medium in a printing press varies significantly over time. For example, if the pneumatic elements of a printing press are used only for regulating functions and automation and not in the actual printing operation, compressed air will be consumed in a short period of time, but consumption over a long period of time will result in leakage loss. It is almost zero if you disregard. Therefore, a continuous air producing press system is not suitable due to inefficiency.

DE-A-2047960 describes a controller for a constant pressure fluid pressure plant in which a plurality of pressure reservoirs are boosted on the inlet side by a constant pressure pump to various pressure values. On the outlet side, a reversing valve device is provided downstream of the pressure store, and these can be used to connect the device to the pressure store according to the load of the device. With this fluid pressure plant, it is possible to exert on each of several loads connected in parallel, the pressure of the pressure vessel corresponding to their actual load conditions. The disadvantage of this method is that since the pressure vessels have different pressures, either mechanical vessels must be provided to accommodate those pressures or they must be fixed to a vessel size designed for maximum pressure. The pressure supply to the container is performed by a pressure-controlled 4/3 conduit switching valve device. These valve devices are activated each time the pressure limit of the respective container is reached. The supply of pressure to the vessels and loads is independent of the control of the system to which these loads are assigned.

In the device described in DE-OS 1503415 for regulating the supply of compressed air from a compressor to a plurality of compressed air reservoirs of a pneumatic plant, between the compressor and the compressed air reservoirs. Is equipped with a check valve. In this case, the check valve is in the drive chamber of the pressure regulator. These check valves are operated by a differential pressure and only serve as a check valve for the compressed air reservoir and the pressure balancing chamber, which is directly pressure supplied by the compressor. In this method, the check valve is not controlled in response to a signal coming from a system with a load connected to the compressed air reservoir.

German Patent Application Publication No. 3300493A1
The pressure supply device for multiple loads according to No. 1 contains one controller for one valve device. The control device activates the valve means when the pressure of the second load drops below a predetermined limit value and restores it again after a short time. By doing so, the pressure chamber is connected to the pressure source or the storage chamber, depending on the predetermined state of the second load. In this method, two circuits of pressure medium separated by a medium carrier are provided to supply pressure to the two loads. that time,
Only one pressure source with a pump is required as the supply means.
The disadvantage of this device is that the first load is supplied directly from the pump, so this pump must always be in operation, and the separation of the two supply circuits is both material and costly.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a system having a modular construction which corresponds to the actual required amount of pressure medium according to the progress of the working process in the printing press over time. To develop a plant for supplying gas under pressure to a printing press system driven by a pressure medium, which makes it possible to supply pressure. Furthermore, the present invention detects malfunctions and leak points in the plant, and even if a part of the system driven by the pressure medium fails, the printing machine can continue to operate in an emergency operation. To provide.

[0008]

To achieve the above object, the device of the present invention comprises at least one compressor, a plurality of pressure reservoirs with pressure gauges, and a distribution or supply of pressure medium. In a pressure supply plant with a device, the system of the printing press driven by a pressure medium is assigned at least one pressure reservoir and a measured value transducer for detecting the pressure of the system. Furthermore, in order to achieve the above-mentioned object, the pressure reservoir can be connected in star-shaped fashion with at least one compressor via an electrically driven pressure medium distributor or feeder. Furthermore, an electrical control unit for the drive unit and the drive motor of the compressor is provided,
The controller is associated with the output of the measured value converter and the machine controller of the printing press. The electric pressure control means and the mechanical control means can form a unit.

[0009]

By using the present invention, it is possible to make a modular compressed air system. In this case, one module is assigned to each sub-unit or only a part thereof, and a non-observable pressure vessel is assigned to this module. When adding another sub-unit to the printing press, the storage capacity available will increase, since the module with the pressure vessel described above will be added. If one compressor is not sufficient to supply a press with many sub-units, multiple compressors may be provided at the end of the same star fluid circuit depending on the size of the machine. Can be connected in parallel via.

The pressure controller and the machine controller regulate the different sporadic required air volumes at different times in different systems driven by the pressure medium to monitor the entire plant and to deal with corresponding defects and service indications. Can be shown.

In order to localize the defects in the plant, each system driven by a pressure medium can be connected to at least one of the pressure vessels via a 5/3 line switching valve with a closed central position. Is a good idea.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a schematic diagram of a pressure supply plant for a printing press 1. The printing press 1 has its own machine control 2, which is connected via a control line 3 to a load, a control valve and an electrical drive of a battery 4. . The load arranged in the printing press 1 is connected to the load / control valve / battery 4 via the work line 5. In addition, the pressure supply plant contains at least one compressor 7 driven by an electric motor 6. The compressor 7 draws in air via the filter 8 and the compressed air is sent via the check valve 9 to the collecting line 10. Further, the printing unit 11 of the printing press 1 includes a relief valve 1
One pressure vessel 12 with 3 is provided for each. The pressure vessel 12 is connected to the outlet line 14 of the control valve 15, and the inlet line 16 of the control valve 15 is connected to the collecting line 10. The load side of the pressure vessel 12 is connected to the load / control valve / supply line 17 of the battery 4. At that time, the pressure limiter 18 is connected to the supply line 17. Each pressure vessel 12 is provided with a pressure gauge 19 that converts pressure into an electric signal. The pressure control unit 20 includes an electromagnetic operation element of the control valve 15 via a lead wire 21, an electric motor 6 of the compressor 7 via a lead wire 22, an output end of the pressure gauge 19 via a lead wire 23,
Then, it is connected to the machine control unit 2 via a conductor 24. The function of the plant will be described below.

The compressor 7, or if necessary a plurality of compressors 7, raises one or a plurality of pressure vessels 12 to a preset working pressure. For that purpose, the corresponding control valve 15 is switched to passing by the pressure control unit 20 on demand. The individual printing units 11 have different air demands at different times, which cannot be fully covered by the capacity of the pressure vessels 12 assigned to each printing unit 11. The compressed air required amount required for the work process proceeding in the printing press 1 and the subsequent work processes can be stored in the machine control unit 2 or the pressure control unit 20, or can be calculated by these. Therefore, the pressure control unit 20 cooperates with the machine control unit 2 to control the electric motor 6 and the control valve 15 so as to supply compressed air to process the next working process. Only one pressure vessel can be pressurized. Also, the air demand of one printing unit 11 or other load is so large that the capacity of one pressure vessel 12 or one compressor 7 is not sufficient, and after that it is also temporarily sufficient at the position of another load. If compressed air must be used and not all pressure vessels 12 should be evacuated at the same time, it is possible to connect a plurality of pressure vessels 12 in parallel using the pressure control unit 20.

Since this plant offers various possibilities for controlling the electric motor 6, the control valve 15 and the load / control valve / battery 4, the plant can be operated at low cost. Due to the modular structure, the plant can be easily expanded. If each printing unit 11 or partial unit is provided with a module consisting of an electric motor 6, a compressor 7, a pressure vessel 12, a load / control valve / battery 4, and accessories, the plant is a module. It can be expanded freely, increasing the total capacity of the pressure vessel.

The control valve 15 and the load / control valve / battery 4 supply compressed air to exactly one load via only one module so that the location of the leak point in the plant can be easily located. it can. in this case,
The corresponding pressure gauge 19 measures the pressure loss at a particular time.

In this plant, the operating cylinder 2 in FIG.
Advantageously, a 5/3 line switching valve 25 is used, as is connected in series with 6. The central position is closed 5
The / 3 pipe line switching valve 25 is a load / control valve / battery 4
The operating cylinder 26 can be shut off from the compressed air supply. For example, the operating cylinder 26
Alternatively, if there is a leak in the supply line 27, an unacceptable high pressure drop in a certain unit time can be evaluated by the pressure control unit 20 via the pressure gauge 19 as described above. At this time, the pressure control unit 20 can place the 5/3 line switching valve 25 in the central position via the control line 28, so that the operation of the operating cylinder 26 is stopped due to the leak point, and the corresponding load / control is performed. Other loads connected to the valve / battery 4 can continue to operate without pressure drop. In this way, the emergency operation of the printing press 1 can be maintained even if the individual operating cylinders 26 or the supply lines 27 fail.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a plant according to the present invention.

FIG. 2 is an embodiment using a 5/3 conduit switching valve.

[Explanation of symbols]

 1 Printing Machine 2 Machine Control Section 3 Control Pipeline 4 Load / Control Valve / Battery 5 Operating Pipeline 6 Electric Motor 7 Compressor 8 Filter 9 Check Valve 10 Collection Pipeline 11 Printing Unit 12 Pressure Vessel 13 Relief Valve 14 Outlet Pipeline 15 Control Valve 16 Inlet Pipeline 17 Supply Pipeline 18 Pressure Limiter 19 Pressure Gauge 20 Pressure Control Unit 21, 22, 23, 24 Signal Line 25 5/3 Pipeline Switching Valve 26 Operating Cylinder 27 Supply Pipeline 28 Control Line

Claims (2)

[Claims] 1. A system for a printing press driven by a pressure medium, which uses at least one compressor and a plurality of pressure reservoirs with pressure gauges, and which uses a pressure medium distributor or feeder. In a plant supplying pressurized gas, each system (11) is assigned at least one pressure reservoir (12) and a measured value transducer (19) for detecting the pressure of the system, The reservoir (12) is at least one compressor (7) via a distributor and supply device (15) for electrically driven pressure medium on the supply side.
Can be combined in the form of a star and the output of the measured value converter (19) and the machine control (2) of the printing machine (1).
Electrical control means (20) are provided for the drive of the distribution and supply device of the pressure medium and for the drive motor (6) of the compressor (7) in connection with A plant to do. 2. A 5/3 line switching valve (25) with a closed central position between the pressure store (12) and the respective system (26) as a distribution and supply device for the pressure medium.
The plant according to claim 1, wherein the plant is provided.